Mesothelioma: The disease that strikes 40 years later

Mesothelioma is a rare form of cancer that develops in the cells that form the linings of the body's chest and abdominal cavities. Although mesothelioma is very rarely seen in the population as a whole in the United Sates, it is found almost exclusively in those who came into repeated contact with asbestos, or materials such as insulation materials that contained asbestos, during their employment or while serving in the Armed Forces. In fact, mesothelioma is so closely associated with occupational exposure to asbestos that it was banned from commercial use in the United States in 1989, although most manufacturers had voluntarily stopped using asbestos-containing materials over a decade earlier. Because it may not appear until many years after the victim's last exposure to asbestos, mesothelioma is often referred to as "the cancer that kills 40 years later."
In addition to mesothelioma, asbestos has been linked with a greater incidence in cancers arising from the lung tissue itself and there is evidence that asbestos may be associated with increased risks of cancers involving the esophagus and the stomach. There appears to be no direct evidence linking cigarette smoking with mesothelioma, aside from the overall increased risks in the occurrence of all forms of cancer that has long been noted among smokers.

The symptoms related to mesothelioma are directly related to the region of the body where the cancer arises. Among the mesotheliomas that develop in the chest cavity, shortness of breath and/or a cough that does not respond to routine treatment are often the only signs that the disease may be present. Often, mesothelioma is discovered only after x-rays have been taken in order to evaluate the victim for other symptoms. Mesotheliomas that develop in the abdomen are usually discovered only after they cause abdominal pain, or anemia, or have grown large enough to cause an intestinal obstruction.

Mesothelioma is notorious among oncologists, physicians who specialize in the treatment of cancer, for being very difficult to treat with any degree of long-term success, although the exact reasons for this remain unclear. Based on the latest data available from the National Institutes of Health's National Cancer Institute, only about 15 to 20 per cent of those diagnosed with mesothelioma this year can be expected to survive for 5 years despite aggressive surgical and medical treatment.